Question

I am currently trying to populate a treeview from xml that is returned to me from a web request. When the response comes in I am manipulating the data so that the XML is in this layout:

<GroupList>
    <Group>
        <GroupName>my first test group</GroupName>
        <GroupID>djnsldgnljsdngljsdngljns</GroupID>
        <AccessLevel>high</AccessLevel>
        <SubGroup>
            <SubGroupName>my first test subgroup</SubGroupName>
            <SubGroupID>djnsldgnljsdngljsdngljns</SubGroupID>
        </SubGroup>
    </Group>
    <Group>
        <GroupName>my second test group</GroupName>
        <GroupID>djnsldgnljsdngljsdngl</GroupID>
        <AccessLevel>high</AccessLevel>
        <SubGroup>
            <SubGroupName>my second test subgroup</SubGroupName>
            <SubGroupID>DBXRdjnsldgnljsdngljsdngl</SubGroupID>
        </SubGroup>
        <SubGroup>
            <SubGroupName>my second test subgroup1</SubGroupName>
            <SubGroupID>EJdjnsldgnljsdngljsdngl42</SubGroupID>
        </SubGroup>
    </Group>
</GroupList>

All I want to do is display the groupName and then you are able to expand and view the subgroups. Currently I have got it “sort of” working but its all in one linear view. Here is my code I currently have:

  xmlDoc.LoadXml(response2);

  groupsTreeView.Nodes.Clear();
  groupsTreeView.Nodes.Add(new
  TreeNode(xmlDoc.DocumentElement.InnerText));
  TreeNode tNode = new TreeNode();
  tNode = (TreeNode)groupsTreeView.Nodes[0];

  addTreeNode(xmlDoc.DocumentElement, tNode);

  groupsTreeView.ExpandAll();

//This function is called recursively until all nodes are loaded
    private void addTreeNode(XmlNode xmlNode, TreeNode treeNode)
    {
        XmlNode xNode;
        TreeNode tNode;
        XmlNodeList xNodeList;
        if (xmlNode.HasChildNodes) //The current node has children
        {
            xNodeList = xmlNode.ChildNodes;

            for (int x = 0; x <= xNodeList.Count - 1; x++)
            //Loop through the child nodes
            {
                xNode = xmlNode.ChildNodes[x];
                groupsTreeView.Nodes.Add(new TreeNode(xNode.Value));
                tNode = groupsTreeView.Nodes[x];
                addTreeNode(xNode, tNode);
            }
        }
        else //No children, so add the outer xml (trimming off whitespace)
            treeNode.Text = xmlNode.OuterXml.Trim();
    }

This image is what the above code looks like when browsed on my system locally:

Any suggestions, im quite lost and it’s doing my head in!

Answer 1

You could try using this using the linq xml(System.Xml.Linq):

    private TreeNode TNGroups(XElement xml)
    {
        TreeNode node = new TreeNode();
        foreach (XElement group in xml.Descendants("Group"))
        {
            TreeNode tnGroup = new TreeNode(group.Element("GroupName").Value);
            node.Nodes.Add(tnGroup);
            foreach (XElement subgroup in group.Elements("SubGroup"))
            {
                TreeNode tnSubGroup = new TreeNode(subgroup.Element("SubGroupName").Value);
                tnGroup.Nodes.Add(tnSubGroup);
            }
        }
        return node;
    }

You would call it like this myTreeView.Nodes.Add(TNGroups(groupsXML)).

To load you XML into an element just use XElement.Load.